/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */ /* dbus-sysdeps.h Wrappers around system/libc features (internal to D-Bus implementation) * * Copyright (C) 2002, 2003 Red Hat, Inc. * Copyright (C) 2003 CodeFactory AB * * SPDX-License-Identifier: AFL-2.1 OR GPL-2.0-or-later * * Licensed under the Academic Free License version 2.1 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifndef DBUS_SYSDEPS_H #define DBUS_SYSDEPS_H #ifndef VERSION #warning Please include config.h before dbus-sysdeps.h #include "config.h" #endif #include #ifdef HAVE_INTTYPES_H #include #endif #include #include #include /* this is perhaps bogus, but strcmp() etc. are faster if we use the * stuff straight out of string.h, so have this here for now. */ #include #include #if !defined(BROKEN_POLL) && (defined(__APPLE__) || defined(__INTERIX)) /* Following libcurl's example, we blacklist poll() on Darwin * (macOS, iOS, etc.) and Interix due to a history of implementation * issues. * https://github.com/curl/curl/blob/master/m4/curl-functions.m4 * * On unspecified older macOS versions, poll() failed if given a * device node to poll. * * On macOS < 10.9, poll() with nfds=0 failed instead of waiting for * the timeout and then succeeding. * * On macOS >= 10.12, poll() with nfds=0 succeeded immediately * instead of waiting for the timeout, resulting in busy-looping. * * On Interix, poll() apparently only works for files in /proc. * * The "legacy" build flavour in our CI machinery defines BROKEN_POLL * on whatever platform is in use (normally Linux) to force use of the * same select()-based poll() emulation that we use for macOS, Interix, * and any platform that lacks a real poll(), so that we can test it * more regularly. */ # define BROKEN_POLL #endif /* Normally we'd only include this in dbus-sysdeps-unix.c. * However, the member names in DBusPollFD are (deliberately) the same as * in POSIX struct pollfd, and AIX's poll() implementation is known to * do things like "#define events reqevents", which would break that approach. * Defend against that by ensuring that if it's renamed anywhere, it's renamed * everywhere. */ #ifdef HAVE_POLL #include #endif #ifdef DBUS_WINCE /* Windows CE lacks some system functions (such as errno and clock). We bring them in here. */ #include "dbus-sysdeps-wince-glue.h" #endif #ifdef DBUS_WIN #include #endif DBUS_BEGIN_DECLS #ifdef DBUS_WIN #define _DBUS_PATH_SEPARATOR ";" #else #define _DBUS_PATH_SEPARATOR ":" #endif /* Forward declarations */ /** An opaque list type */ typedef struct DBusList DBusList; /** Object that contains a list of credentials such as UNIX or Windows user ID */ typedef struct DBusCredentials DBusCredentials; /** A wrapper around a pipe descriptor or handle */ typedef struct DBusPipe DBusPipe; /** * @addtogroup DBusSysdeps * * @{ */ DBUS_PRIVATE_EXPORT void _dbus_abort (void) _DBUS_GNUC_NORETURN; dbus_bool_t _dbus_check_setuid (void); DBUS_PRIVATE_EXPORT const char* _dbus_getenv (const char *varname); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_clearenv (void); char ** _dbus_get_environment (void); /** A process ID */ typedef unsigned long dbus_pid_t; /** A user ID */ typedef unsigned long dbus_uid_t; /** A group ID */ typedef unsigned long dbus_gid_t; /** an invalid PID used to represent an uninitialized dbus_pid_t field */ #define DBUS_PID_UNSET ((dbus_pid_t) -1) /** an invalid UID used to represent an uninitialized dbus_uid_t field */ #define DBUS_UID_UNSET ((dbus_uid_t) -1) /** an invalid GID used to represent an uninitialized dbus_gid_t field */ #define DBUS_GID_UNSET ((dbus_gid_t) -1) /** an appropriate printf format for dbus_pid_t */ #define DBUS_PID_FORMAT "%lu" /** an appropriate printf format for dbus_uid_t */ #define DBUS_UID_FORMAT "%lu" /** an appropriate printf format for dbus_gid_t */ #define DBUS_GID_FORMAT "%lu" /** * Socket interface */ #ifdef DBUS_WIN typedef struct { SOCKET sock; } DBusSocket; # define DBUS_SOCKET_FORMAT "Iu" # define DBUS_SOCKET_INIT { INVALID_SOCKET } _DBUS_WARN_UNUSED_RESULT static inline SOCKET _dbus_socket_printable (DBusSocket s) { return s.sock; } _DBUS_WARN_UNUSED_RESULT static inline dbus_bool_t _dbus_socket_is_valid (DBusSocket s) { return s.sock != INVALID_SOCKET; } static inline void _dbus_socket_invalidate (DBusSocket *s) { s->sock = INVALID_SOCKET; } _DBUS_WARN_UNUSED_RESULT static inline int _dbus_socket_get_int (DBusSocket s) { return (int)s.sock; } #else /* not DBUS_WIN */ typedef struct { int fd; } DBusSocket; # define DBUS_SOCKET_FORMAT "d" # define DBUS_SOCKET_INIT { -1 } _DBUS_WARN_UNUSED_RESULT static inline int _dbus_socket_printable (DBusSocket s) { return s.fd; } _DBUS_WARN_UNUSED_RESULT static inline dbus_bool_t _dbus_socket_is_valid (DBusSocket s) { return s.fd >= 0; } static inline void _dbus_socket_invalidate (DBusSocket *s) { s->fd = -1; } _DBUS_WARN_UNUSED_RESULT static inline int _dbus_socket_get_int (DBusSocket s) { return s.fd; } #endif /* not DBUS_WIN */ _DBUS_WARN_UNUSED_RESULT static inline DBusSocket _dbus_socket_get_invalid (void) { DBusSocket s = DBUS_SOCKET_INIT; return s; } dbus_bool_t _dbus_set_socket_nonblocking (DBusSocket fd, DBusError *error); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_close_socket (DBusSocket *fd, DBusError *error); DBUS_PRIVATE_EXPORT int _dbus_read_socket (DBusSocket fd, DBusString *buffer, int count); DBUS_PRIVATE_EXPORT int _dbus_write_socket (DBusSocket fd, const DBusString *buffer, int start, int len); int _dbus_write_socket_two (DBusSocket fd, const DBusString *buffer1, int start1, int len1, const DBusString *buffer2, int start2, int len2); int _dbus_read_socket_with_unix_fds (DBusSocket fd, DBusString *buffer, int count, int *fds, unsigned int *n_fds); DBUS_PRIVATE_EXPORT int _dbus_write_socket_with_unix_fds (DBusSocket fd, const DBusString *buffer, int start, int len, const int *fds, int n_fds); int _dbus_write_socket_with_unix_fds_two (DBusSocket fd, const DBusString *buffer1, int start1, int len1, const DBusString *buffer2, int start2, int len2, const int *fds, int n_fds); DBusSocket _dbus_connect_tcp_socket (const char *host, const char *port, const char *family, DBusError *error); DBusSocket _dbus_connect_tcp_socket_with_nonce (const char *host, const char *port, const char *family, const char *noncefile, DBusError *error); int _dbus_listen_tcp_socket (const char *host, const char *port, const char *family, DBusString *retport, const char **retfamily, DBusSocket **fds_p, DBusError *error); DBusSocket _dbus_accept (DBusSocket listen_fd); dbus_bool_t _dbus_read_credentials_socket (DBusSocket client_fd, DBusCredentials *credentials, DBusError *error); dbus_bool_t _dbus_send_credentials_socket (DBusSocket server_fd, DBusError *error); typedef enum { DBUS_CREDENTIALS_ADD_FLAGS_USER_DATABASE = (1 << 0), DBUS_CREDENTIALS_ADD_FLAGS_NONE = 0 } DBusCredentialsAddFlags; dbus_bool_t _dbus_credentials_add_from_user (DBusCredentials *credentials, const DBusString *username, DBusCredentialsAddFlags flags, DBusError *error); dbus_bool_t _dbus_credentials_add_from_current_process (DBusCredentials *credentials); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_append_user_from_current_process (DBusString *str); dbus_bool_t _dbus_parse_unix_user_from_config (const DBusString *username, dbus_uid_t *uid_p); dbus_bool_t _dbus_parse_unix_group_from_config (const DBusString *groupname, dbus_gid_t *gid_p); dbus_bool_t _dbus_unix_groups_from_uid (dbus_uid_t uid, dbus_gid_t **group_ids, int *n_group_ids); dbus_bool_t _dbus_unix_user_is_at_console (dbus_uid_t uid, DBusError *error); dbus_bool_t _dbus_unix_user_is_process_owner (dbus_uid_t uid); dbus_bool_t _dbus_windows_user_is_process_owner (const char *windows_sid); dbus_bool_t _dbus_append_keyring_directory_for_credentials (DBusString *directory, DBusCredentials *credentials); dbus_bool_t _dbus_daemon_unpublish_session_bus_address (void); dbus_bool_t _dbus_socket_can_pass_unix_fd(DBusSocket fd); /** Opaque type representing an atomically-modifiable integer * that can be used from multiple threads. */ typedef struct DBusAtomic DBusAtomic; /** * An atomic integer safe to increment or decrement from multiple threads. */ struct DBusAtomic { #ifdef DBUS_WIN volatile long value; /**< Value of the atomic integer. */ #else volatile dbus_int32_t value; /**< Value of the atomic integer. */ #endif }; DBUS_PRIVATE_EXPORT dbus_int32_t _dbus_atomic_inc (DBusAtomic *atomic); DBUS_PRIVATE_EXPORT dbus_int32_t _dbus_atomic_dec (DBusAtomic *atomic); DBUS_PRIVATE_EXPORT dbus_int32_t _dbus_atomic_get (DBusAtomic *atomic); DBUS_PRIVATE_EXPORT void _dbus_atomic_set_zero (DBusAtomic *atomic); DBUS_PRIVATE_EXPORT void _dbus_atomic_set_nonzero (DBusAtomic *atomic); #ifdef DBUS_WIN /* On Windows, you can only poll sockets. We emulate Unix poll() using * select(), so it doesn't matter what precise type we put in DBusPollFD; * use DBusSocket so that the compiler can check we are doing it right. */ typedef DBusSocket DBusPollable; # define DBUS_POLLABLE_FORMAT "Iu" static inline DBusPollable _dbus_socket_get_pollable (DBusSocket s) { return s; } static inline SOCKET _dbus_pollable_printable (DBusPollable p) { return p.sock; } static inline dbus_bool_t _dbus_pollable_is_valid (DBusPollable p) { return _dbus_socket_is_valid (p); } static inline void _dbus_pollable_invalidate (DBusPollable *p) { _dbus_socket_invalidate (p); } static inline dbus_bool_t _dbus_pollable_equals (DBusPollable a, DBusPollable b) { return a.sock == b.sock; } #else /* !DBUS_WIN */ /* On Unix, you can poll sockets, pipes, etc., and we must put exactly * "int" in DBusPollFD because we're relying on its layout exactly matching * struct pollfd. (This is silly, and one day we should use a better * abstraction.) */ typedef int DBusPollable; # define DBUS_POLLABLE_FORMAT "d" static inline DBusPollable _dbus_socket_get_pollable (DBusSocket s) { return s.fd; } static inline int _dbus_pollable_printable (DBusPollable p) { return p; } static inline dbus_bool_t _dbus_pollable_is_valid (DBusPollable p) { return p >= 0; } static inline void _dbus_pollable_invalidate (DBusPollable *p) { *p = -1; } static inline dbus_bool_t _dbus_pollable_equals (DBusPollable a, DBusPollable b) { return a == b; } #endif /* !DBUS_WIN */ #if defined(HAVE_POLL) && !defined(BROKEN_POLL) /** * A portable struct pollfd wrapper, or an emulation of struct pollfd * on platforms where poll() is missing or broken. */ typedef struct pollfd DBusPollFD; /** There is data to read */ #define _DBUS_POLLIN POLLIN /** There is urgent data to read */ #define _DBUS_POLLPRI POLLPRI /** Writing now will not block */ #define _DBUS_POLLOUT POLLOUT /** Error condition */ #define _DBUS_POLLERR POLLERR /** Hung up */ #define _DBUS_POLLHUP POLLHUP /** Invalid request: fd not open */ #define _DBUS_POLLNVAL POLLNVAL #else /* Emulate poll() via select(). Because we aren't really going to call * poll(), any similarly-shaped struct is acceptable, and any power of 2 * will do for the events/revents; these values happen to match Linux * and *BSD. */ typedef struct { DBusPollable fd; /**< File descriptor */ short events; /**< Events to poll for */ short revents; /**< Events that occurred */ } DBusPollFD; /** There is data to read */ #define _DBUS_POLLIN 0x0001 /** There is urgent data to read */ #define _DBUS_POLLPRI 0x0002 /** Writing now will not block */ #define _DBUS_POLLOUT 0x0004 /** Error condition */ #define _DBUS_POLLERR 0x0008 /** Hung up */ #define _DBUS_POLLHUP 0x0010 /** Invalid request: fd not open */ #define _DBUS_POLLNVAL 0x0020 #endif DBUS_PRIVATE_EXPORT int _dbus_poll (DBusPollFD *fds, int n_fds, int timeout_milliseconds); DBUS_PRIVATE_EXPORT void _dbus_sleep_milliseconds (int milliseconds); DBUS_PRIVATE_EXPORT void _dbus_get_monotonic_time (long *tv_sec, long *tv_usec); DBUS_PRIVATE_EXPORT void _dbus_get_real_time (long *tv_sec, long *tv_usec); /** * directory interface */ DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_create_directory (const DBusString *filename, DBusError *error); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_ensure_directory (const DBusString *filename, DBusError *error); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_delete_directory (const DBusString *filename, DBusError *error); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_concat_dir_and_file (DBusString *dir, const DBusString *next_component); dbus_bool_t _dbus_string_get_dirname (const DBusString *filename, DBusString *dirname); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_path_is_absolute (const DBusString *filename); dbus_bool_t _dbus_get_standard_session_servicedirs (DBusList **dirs); dbus_bool_t _dbus_get_standard_system_servicedirs (DBusList **dirs); dbus_bool_t _dbus_set_up_transient_session_servicedirs (DBusList **dirs, DBusError *error); dbus_bool_t _dbus_get_system_config_file (DBusString *str); dbus_bool_t _dbus_get_session_config_file (DBusString *str); /** Opaque type for reading a directory listing */ typedef struct DBusDirIter DBusDirIter; DBusDirIter* _dbus_directory_open (const DBusString *filename, DBusError *error); dbus_bool_t _dbus_directory_get_next_file (DBusDirIter *iter, DBusString *filename, DBusError *error); void _dbus_directory_close (DBusDirIter *iter); dbus_bool_t _dbus_check_dir_is_private_to_user (DBusString *dir, DBusError *error); DBUS_PRIVATE_EXPORT const char* _dbus_get_tmpdir (void); /** * Random numbers */ _DBUS_WARN_UNUSED_RESULT dbus_bool_t _dbus_generate_random_bytes_buffer (char *buffer, int n_bytes, DBusError *error); dbus_bool_t _dbus_generate_random_bytes (DBusString *str, int n_bytes, DBusError *error); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_generate_random_ascii (DBusString *str, int n_bytes, DBusError *error); DBUS_PRIVATE_EXPORT const char* _dbus_error_from_errno (int error_number); DBUS_PRIVATE_EXPORT const char* _dbus_error_from_system_errno (void); int _dbus_get_low_level_socket_errno (void); int _dbus_save_socket_errno (void); void _dbus_restore_socket_errno (int saved_errno); void _dbus_set_errno_to_zero (void); dbus_bool_t _dbus_get_is_errno_eagain_or_ewouldblock (int e); dbus_bool_t _dbus_get_is_errno_enomem (int e); dbus_bool_t _dbus_get_is_errno_eintr (int e); dbus_bool_t _dbus_get_is_errno_epipe (int e); dbus_bool_t _dbus_get_is_errno_etoomanyrefs (int e); DBUS_PRIVATE_EXPORT const char* _dbus_strerror_from_errno (void); void _dbus_disable_sigpipe (void); DBUS_PRIVATE_EXPORT void _dbus_exit (int code) _DBUS_GNUC_NORETURN; DBUS_PRIVATE_EXPORT int _dbus_printf_string_upper_bound (const char *format, va_list args) _DBUS_GNUC_PRINTF (1, 0); #ifdef DBUS_ENABLE_VERBOSE_MODE DBUS_PRIVATE_EXPORT void _dbus_print_thread (void); #endif /** * Portable struct with stat() results */ typedef struct { unsigned long mode; /**< File mode */ unsigned long nlink; /**< Number of hard links */ dbus_uid_t uid; /**< User owning file */ dbus_gid_t gid; /**< Group owning file */ unsigned long size; /**< Size of file */ unsigned long atime; /**< Access time */ unsigned long mtime; /**< Modify time */ unsigned long ctime; /**< Creation time */ } DBusStat; dbus_bool_t _dbus_stat (const DBusString *filename, DBusStat *statbuf, DBusError *error); DBusSocket _dbus_connect_unix_socket (const char *path, dbus_bool_t abstract, DBusError *error); DBusSocket _dbus_listen_unix_socket (const char *path, dbus_bool_t abstract, DBusError *error); DBusSocket _dbus_connect_exec (const char *path, char *const argv[], DBusError *error); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_socketpair (DBusSocket *fd1, DBusSocket *fd2, dbus_bool_t blocking, DBusError *error); DBUS_PRIVATE_EXPORT void _dbus_print_backtrace (void); dbus_bool_t _dbus_become_daemon (const DBusString *pidfile, DBusPipe *print_pid_pipe, DBusError *error, dbus_bool_t keep_umask); dbus_bool_t _dbus_verify_daemon_user (const char *user); dbus_bool_t _dbus_change_to_daemon_user (const char *user, DBusError *error); dbus_bool_t _dbus_write_pid_to_file_and_pipe (const DBusString *pidfile, DBusPipe *print_pid_pipe, dbus_pid_t pid_to_write, DBusError *error); dbus_bool_t _dbus_command_for_pid (unsigned long pid, DBusString *str, int max_len, DBusError *error); typedef enum { DBUS_LOG_FLAGS_STDERR = (1 << 0), DBUS_LOG_FLAGS_SYSTEM_LOG = (1 << 1) } DBusLogFlags; DBUS_PRIVATE_EXPORT void _dbus_init_system_log (const char *tag, DBusLogFlags flags); typedef enum { DBUS_SYSTEM_LOG_INFO, DBUS_SYSTEM_LOG_WARNING, DBUS_SYSTEM_LOG_SECURITY, DBUS_SYSTEM_LOG_ERROR } DBusSystemLogSeverity; DBUS_PRIVATE_EXPORT void _dbus_log (DBusSystemLogSeverity severity, const char *msg, ...) _DBUS_GNUC_PRINTF (2, 3); DBUS_PRIVATE_EXPORT void _dbus_logv (DBusSystemLogSeverity severity, const char *msg, va_list args) _DBUS_GNUC_PRINTF (2, 0); /** On x86 there is an 80-bit FPU, and if you do "a == b" it may have a * or b in an 80-bit register, thus failing to compare the two 64-bit * doubles for bitwise equality. So this macro compares the two doubles * bitwise. */ #define _DBUS_DOUBLES_BITWISE_EQUAL(a, b) (memcmp (&(a), &(b), sizeof (double)) == 0) dbus_bool_t _dbus_get_autolaunch_address (const char *scope, DBusString *address, DBusError *error); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_lookup_session_address (dbus_bool_t *supported, DBusString *address, DBusError *error); /** Type representing a universally unique ID * @todo rename to UUID instead of GUID */ typedef union DBusGUID DBusGUID; DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_read_local_machine_uuid (DBusGUID *machine_id, dbus_bool_t create_if_not_found, DBusError *error); /** * Initialize threads as in dbus_threads_init_default(), appropriately * for the platform. * @returns #FALSE if no memory */ dbus_bool_t _dbus_threads_init_platform_specific (void); /** * Lock a static mutex used to protect _dbus_threads_init_platform_specific(). */ void _dbus_threads_lock_platform_specific (void); /** * Undo _dbus_threads_lock_platform_specific(). */ void _dbus_threads_unlock_platform_specific (void); DBUS_PRIVATE_EXPORT dbus_bool_t _dbus_split_paths_and_append (DBusString *dirs, const char *suffix, DBusList **dir_list); unsigned long _dbus_pid_for_log (void); /* FIXME move back to dbus-sysdeps-unix.h probably - * the PID file handling just needs a little more abstraction * in the bus daemon first. */ DBUS_PRIVATE_EXPORT dbus_pid_t _dbus_getpid (void); DBUS_PRIVATE_EXPORT dbus_uid_t _dbus_getuid (void); DBUS_PRIVATE_EXPORT void _dbus_flush_caches (void); dbus_bool_t _dbus_replace_install_prefix (DBusString *path); /* Do not set this too high: it is a denial-of-service risk. * See * * (This needs to be in the non-Unix-specific header so that * the config-parser can use it.) */ #define DBUS_DEFAULT_MESSAGE_UNIX_FDS 16 typedef struct DBusRLimit DBusRLimit; DBusRLimit *_dbus_rlimit_save_fd_limit (DBusError *error); dbus_bool_t _dbus_rlimit_raise_fd_limit (DBusError *error); dbus_bool_t _dbus_rlimit_restore_fd_limit (DBusRLimit *saved, DBusError *error); void _dbus_rlimit_free (DBusRLimit *lim); void _dbus_daemon_report_ready (void); void _dbus_daemon_report_reloading (void); void _dbus_daemon_report_reloaded (void); void _dbus_daemon_report_stopping (void); dbus_bool_t _dbus_inet_sockaddr_to_string (const void *sockaddr_pointer, size_t len, char *string, size_t string_len, const char **family_name, dbus_uint16_t *port, DBusError *error); void _dbus_set_error_with_inet_sockaddr (DBusError *error, const void *sockaddr_pointer, size_t len, const char *description, int saved_errno); void _dbus_combine_tcp_errors (DBusList **sources, const char *summary, const char *host, const char *port, DBusError *dest); /** * @def _DBUS_MAX_SUN_PATH_LENGTH * * Maximum length of the path to a UNIX domain socket, * sockaddr_un::sun_path member. POSIX requires that all systems * support at least 100 bytes here, including the nul termination. * We use 99 for the max value to allow for the nul. * * We could probably also do sizeof (addr.sun_path) * but this way we are the same on all platforms * which is probably a good idea. */ #define _DBUS_MAX_SUN_PATH_LENGTH 99 /** @} */ DBUS_END_DECLS #ifdef DBUS_WIN #include "dbus-sysdeps-win.h" #endif #endif /* DBUS_SYSDEPS_H */